INDUSTRIAL APPLICATIONS OF HIGH CURRENT CHOPPER RECTIFIERS: STATE OF THE ART

This paper discusses the use of choppers with Insulated Gate Bipolar Transistors in conjunction with non-controlled diode rectifiers, to generate large controlled currents. These converters are known as Chopper Rectifiers and are a new possibility in the generation of currents in the kiloamperes range. The paper presents the basic principles, the main characteristics and a comparison to phase controlled rectifiers with thyristors. Chopper rectifiers generate a load current with reduced ripple and they operate with a high and constant power factor. In addition, they generate few input current harmonics and operate without passive filters. The paper also includes an efficiency assessment versus thyristor rectifiers and presents a reference list of units installed by two major manufacturers. The main conclusion of the paper is that these new rectifiers are very attractive from a technical point of view.